Method of increasing tensile properties of viscose rayon



Patented Dec. 10, 1935 METHOD OF INCREASING TENSILE reor- ERTIES orVISCOSE' apron James Willard Humphrey, Claymont, Del., and John WatsonPedlow, Chester, Pa., assignors to The Viscose Company, Marcus Hook,Pat, a corporation of Pennsylvania No Drawing. Application November 12.1934, Serial No. 752,784

13 Claims. (Cl. 1106-40) This application is in part a continuation orour copend-ing application of the same title, Serial No. 657,464, filedFebruary 18th, 1933.

The object of our invention is to produce viscose rayon having increasedtensile properties.

We have discovered that by adding to the viscose solution organicliquids which do not substantially remain with the finished rayon, butinstead are almost entirely lost during the spinning operation when spunin the usual manner, we can produce viscose rayon having greater tensilestrength than normal yarn, and also having a marked increase insoftness, but without pronounced difierence in dye absorbing capacity orgeneral appearance.

Generically, in carrying out our invention, we add to the viscosesolution one or more of a group of materials which we have discovered tobe operative for this purpose, and then carry out the spinning operationin the usual manner. This group of materials, all of which are operativefor our purpose, consists in those aromatic derivatives of the aliphaticalcohols in which a hydrogen atom which is attached directly to a.carbon atom has been replaced by an aromatic group. In other words, thearomatic group has been substituted for a hydrogen atom other than thatof the hydroxyl group of the alcohol.

As a sub-genus of the broad class of compounds disclosed above as beingoperative for our purpose, we preier the phenyl derivatives of thealiphatic alcohols, in which the phenyl or phenyl derivative replaces ahydrogen atom other than that of the hydroxyl group of the alcohol.

The viscose solution to which the material is added is normally asolution of cellulose xanthate in dilute alkali, the concentration ofcellulose being from 7 to 8% and the sodium hydroxide from 6 to 8%. Inspinning the solution with the material added thereto the same is pumpedthrough a spinneret into a coagulating bath which generally containsaround 8% sulphuric acid, 12% sodium sulphate and it may also containfrom to 15% glucose and also .2 to 1.5% zinc sulphate. It is understoodthat the composition of the viscose solution and the composition of thecoagulating bath as given above are merely by way of illustration ofcurrent plant practice and that the proper functioning of the materialadded according to the present invention to produce a stronger andsofter yarn is by no means limited to such conditions.

The increase in tensile properties is in proportion to the amount ofmaterial added, and can be as high as 35% increase in wet strength,

increase in dry strength, and 20% increase in dry extensibility. Withlarger amounts of material added these strengths may be increasedfurther, but for economical reasons we prefer to add the material inamount of 1% to 2% by weight on 5 the viscose solution, or approximatelyto 80% on the basis of the cellulose present in the viscose. The majorportion of the material so added apparently does not remain with thefinished yarn, but is almost entirely lost during the spinningoperation. The added material largely disappears from the yarn duringthe spin ning operation and thus is positively removed from the extrudedfilament.

As representative and illustrative of the group of materialshereinbefore disclosed as operative for our purpose, the followingspecific members of the broad group are given by way of exam ple:

1. Anisyl alcohol, which may be considered as methyl alcohol in which ahydrogen has been replaced by a methoxy phenyl group;

2. Benzyl alcohol, which is methyl alcohol in which a hydrogen has beenreplaced by phenyl only; and

3. Phenyl ethyl alcohol, which is ethyl alcohol in which a hydrogen hasbeen replaced by phenyl;

4. Paraclor benzyl alcohol, which is a methyl alcohol in which ahydrogen atom attached to the carbon atom has been replaced by theparaclor benzene group.

These examples have been selected because they are commerciallyavailable in suitable quantities and at economical prices, and not inderogation of the other members of the disclosed broad class or group.

It is not necessary to have the material soluble in the viscosesolution. For example, 1 benzyl alcohol may be added to the viscose asan emulsion or as the sodium salt which is soluble in the viscosesolution.

As a specific example of the process, viscose solution is prepared asusual, is filtered, aged, and then within 24 hours of the properspinning time, 1 by weight of benzyl alcohol is thoroughly emulsified inthe viscose solution at the proper spinning age and under normalspinning conditions this viscose is then spun, reeled, processed, etc.Tensile tests made on this yarn show that there is an increase in wetstrength of approximately of dry strength approximately 5%, and of dryextensibility of approximately 15%.

What we claim is:

1. Method of increasing tensile properties of viscose rayon whichcomprises adding to the viscose solution an aromatic derivative of analiphatic alcohol, the aromatic group replacing a hydrogen atom otherthan that of the hydroxyl group of the alcohol, the major portion ofwhich does not remain with the extruded filament, but is almost entirelylost during the spinning operation, whereby viscose rayon'is producedhaving materially greater tensile properties than viscose rayonsimilarly spun without the addition and loss of any such material.

2. Method of increasing tensile properties of viscose rayon whichcomprises adding to the viscose solution a phenyl derivative 01. analiphatic alcohol, the phenyl or phenyl derivative grouping replacing ahydrogen atom which is attached directly to a carbon atom whereby asolution is obtained which upon spinning produces viscose rayon'havingmaterially greater tensile properties than viscose rayon similarly spunwithout theaddition of any such material.

.3. Method of increasing tensile properties of viscose rayon whichcomprises adding to the viscose solution a phenyl derivative of anallphatic alcohol, or the group consisting of anisyl, benzyl phenylethyl, and paraclor benzyl alcohols, whereby a solution is obtainedwhich upon spinning produces viscose rayon having materially greatertensile properties than viscose rayon similarly spun without theaddition of any such material.

4. Method of increasing tensile properties of viscose rayon whichcomprises adding to the viscose solution anisyl alcohol, whereby asolution is obtained which upon spinning produces viscose rayon havingmaterially greater tensile properties than viscose rayon similarly spunwithout the addition of any such material.

5. Method of increasing tensile properties of viscose rayon whichcomprises adding to the viscose solution benzyl alcohol, whereby asolution is obtained which upon spinning produces viscose rayon havingmaterially greater tensile properties than viscose rayon similarly spunwithout the addition of any such material.

6. Method of increasing tensile properties of viscose rayon whichcomprises adding to the viscose solution phenyl ethyl alcohol, whereby asolution is obtained which upon spinning produces viscose rayon havingmaterially greater tensile properties than viscose rayon similarly spunwithout the addition of any such material.

7. Viscose solution adapted to be spun into viscose rayon havingincreased tensile properties, and containing an aromatic derivative ofan aliphatic alcohol, the aromatic grouping replacing a hydrogen atomother than that or the hydroxyl group of the alcohol.

8. Viscose solution containing a phenyl derivative of an aliphaticalcohol, the phenyl or phenyl derivative grouping replacing a hydrogenatom which is directly attached to a carbon atom, whereby said solutionis adapted to be spun into viscose rayon of materially greater tensileproperties than viscose rayon produced from viscose solution notcontaining any such material.

9. Viscose solution containing 1% to 2% by weight or approximately 15%to 30% on the basis of the cellulose present in the viscose, of anaromatic derivative of an aliphatic alcohol in which the aromaticgrouping replaces a hydrogen atom other than that of the hydroxyl groupof the alcohol.

10. Viscose solution containing a material from the group consisting ofanisyl, benzyl, phenyl ethyl, and paraclor benzyl alcohols.

- 11. Viscose solution containing anisyl alcohol. 12. Viscose solutioncontaining benzyl alcohol.

13. Viscose solution containing phenyl ethyl

